Process of making seamless-body cans.



, G; W.' WEB-ER. PROCESS 0F MAKING SBAMLESS BODY CANS.- APPLICATION FILED AUG. 5, 1908.

Patented Feb. 14, 1911.

984,173. Original application iiled Ju1y26, 1907, Serial No. 385,631. Divided and this 1908. Serial No. 447,041,

GEORGE W. WEBER, oENEW YORK, N. Y;, assreNoR rro AMERICAN CAN COMPANY, E f NEW YoRK, N. fr., A CORPORATION or NEW JERSEY.

' `PROCESS O MAKING SEAMLESS-BODY CANSi.

' To all 'whom 'it may concern:`

c -Be it known that I, GEORGE lll. lVEER, a

citizen off the United States, residing 1n New York, in the county of New York and State of New York, have invented a new and useful Improvement in Methods or Processes of Making Seamlessody Cans, of which the following isa specification.l

l`My invention relates to improvements in the method' or process of manufacturing seamless body cans.

This application 1s a division of my voriginal application No. 385,631, filed July 26th, 1907, on drawn or seamless lbody cans and method of drawingor making same.

Heretofore in the Apractical manufacture and use of drawn or seamless body cans'for sardines and'other articles, and which are can or the more sharply curved portions' of the oval can, as to render it very difficult or impossible to practically secure with requisite certainty, hermetically tight seams by interfolding the seaming flange of the cover with the seaming flange of the body. And further difliculty is also experienced from the fact that the drawing operation' tends to thin and vfray the tin coating of the tin plate at the upper portion ofthe can body and thus render the tin plate peculiarly liableto attack from acids or alkalis in the food or other contents of the can. Herefofore attempts have been made to lessen vthe ,percent-age of leaky cans incidentto the cracking,4 breaking, wrinkling, puckering or Y roughening of the seaming flange -of the body under the drawing operation by applying to the seaming flange of thev cover an elastic packingor gasket of rubber, paper, rubber'cement and various forms of packing dope and other expediente which 'add materially to the cost of manufacture and which at best only serve to palliate without remov-L ing the cause of the difficulty.

My invention consists in themealis I have discovered for practically removing and Specification of Letters Pate'nt.

frayed or theiron or steel Patented Neb. la, lair.

application filed August 5,

overcoming the difficulties and` objections heretofore experienced, and by which I am enabled to practically produce cheaply and rapidly drawn or seamless body cans having sharply curved corners 'or ends if required, and wherein the seaming flanges thereof will be frec from cracks, or breaks. Wrinkles, puckers or roughnesses, and which when interfolded with the seeming flanges of the covers will form hermetically tight seams. and wherein the tin plate of the body will be at the same time e'ectually protected from attack of' acids or fruit juices in i the food products contained in the can or the contents thereof.

I have discovered that by first applying to the sheets of tin plate in the flat from which the bodies of the cans are to be drawn, acoating of lacquer, preferably the ordinary gold lacquer of commerce, and then baking the` coated sheets of tinplate at a temperature preferably of from three hundred and fifty to live hundred degrees Fahrenheit for a period preferably offromone to five hours,v

and then cutting and drawing the can bodies from such baked lacquered sheets of tin plate, the drawmg'operati'on will not only be greatly facilitated` butsubstantially all liability for the stock to crack or break or to become. wrinkled, puckered or roughened at the upper portion of the can body or at the seaming Aflange' thereof-will be removed or eliminated, and that rat the same time, Vthey drawn can body will be left with a continuous uncracked, unbroken protective coating of baked lacquer'over its entireinterior surface including theupper surface of its "seaming flange, and that this protec/t-ive coating of baked lacquer will also serve to preventtlio tincoating itself underneath from becoming plate beneath the tin coating from becoming dennded of tin and exposed in streaks, and'that the baked lacquer coating will also not only serve to protect the tin plate from attack of acids or alkalis in the contents of the can but also serve as an efficient packing for the folded seam uniting the cover to the can body. The covers are Apreferably also cut and formed from sheets of tin: plate having a similar baked lacquer protective coating. rI he protective coating on themnder surface of the seaming flange Aof the cover in connection with the protective coating on the sheet after the lacquer coating has been can. Fig'S is an enlarged detail section on spective view partly vgreater depth than the sardine can repreupper surface of-the searning Harige of the body thus affords a ydouble packing for the interfolded seam which unites the. cover to the body.

In the accompanying rdrawing forming a part of this specification, Figure l represents a sheet of tin plate in the flat before 1t c is coated with lacquer. Fig. 2 is a similar View lshowing the sheet after it is coated with gold lacquer. Fig. 3 illustrates the baked at a temperature of from three hundred to five hundred degrees Fahrenheit, preferably for two or three hours. Fig. 4 is a perspective view illustratingthe body of a seamless or drawn sardine can formed from the baked lacquered sheet. Fig. 5 is a similar view showing the cover of the can. Figf is a vertical section of the completed can after the cover has been seamed thereon. Fig. 7is an enlarged detail sectional view' through the seam uniting lthe cover to the 8-8 of Fig. 6. Fig. 9 is a detail perin section showing my invention as applied to an oval can of line sented in Fig. 6.

In the drawing, A represents a sheet of tin plate in the flat having vthe customary thin coating of tin a on bot-h sides. Before the can bodies and covers are cut and drawn from the sheet of tin plate A, it is first furnished with a protective coating C of lacquer, preferably gold lacquer, and subjected to a baking step or operation in a suitable oven, preferably at a temperature of about three hundred and fty or four hundred degrees Fahrenheit for a period of two or three hours, which baking operation ,renders the lacquer hard, dry, innocuous, tasteless and free fromodor and causes it to be firmly adherent to the tin plate.

B is the seamless .can body drawn from the baked lacquered sheet of tin plate A and having at its upper end a laterally projecting seaming flange b and furnished in its interior with a protective coating of baked lacquer C which also extends over the upper surface of the seaming flange b.

D is the cover, the saine having a marginal searning flange (l and provided with a baked lacquered preservative coating C on its inner surface extending over the lower face of its seeming flange cZ. The baked lacquer coating C extends continuously and unbrokenly over the entire interior surface of the can body B and upper surface of its seaming flange I) andthe preservative lacquer coating C on the cover D also extends continuously and unbrokenly over the entire inner surface of the cover including` its seaming flange d. i

By reason of the protective baked lacquer coating C on the tin plate A before the saine l is cut and drawn into can bodies, the drawing operation has little and no injurious tendency to crack, break, or to materially or injuriously wrinkle, pucker or roughen the upper portion of the can body including its seaniing lia-nge and leaves the body and its seaininfr flange I) with a continuous unbroken and perfect tin coating a throughout and also with a continuous perfect and unbroken protect-ive baked lacquer coating C throughout, any minute puckers that may exist in the sheet steel of the tin plate or in.v 4the upper surface of the tin coating thereof being neutralized or taken up by the hard,

`dry, baked lacquer coating and not iinparted to the upper surface thereof to any appreciable or recognizable extent. And the same also applies to the tin coating C of the cover D. And the sharply curved portions b1 of the can body at the corners thereof ifit is of rectangular shape, 'or atthe ends thereof if it is of oval or other shape, as shown in Fig. 9, do not cause the seaining flange of the body to crack, break, or to materially or injuriously 'pucker or wrinkle at such sharply curved portions. After the body is drawn to shape, it is preferably furnished with an externally projecting bead b2 near its lower end to give the can body as a whole a symmetrical appearance and to afford a shoulder in conjunction with the folded seam uniting the cover with the body to better hold a label in place on the body. After the can bodies and covers have thus been cut and formed from the baked lacquer protective coated sheets 'of tin plate and the can body has been filled with sardines or other articles, the cover is united'tliereto by interfolding the-seaining ange d of the cover with the seaming flange b of the body, preferably into a double seam E, the double thickness fof protective coating C between the contacting faces of the seaming flanges d serving as an eiicient packing to formf an hermetically tight folded seam E in conjunction with the freedom from cracks, breaks, and substantial freedom from wrinkles, `puckers and roughnesses in such seaining anges due to my improved method of making or dra-wing the can bodies and covers.

l. The method or process, of making hernietically tight seamless drawn body cans which will be proof against attack of acids or alkalis in the can contents, consisting in first coating thelsheets of tin plate of whichthe bodies and covers are to lacquer, then baking thesheets thereby rendering the lacquer fully dry and hard, and ,firmly adherent, innocuous and tasteless, then cutting hand drawing the can bodiesand covers therefrom, said hard, dry, baked lacquer coating serving in said drawing step to diminish and neutralize packers be formed with f 984,173 l it,

in the seam flanges of said bodies and covers X and then folding the sealining flanges of the` bodies and covers together into double seams i .With the baked lacquer protective coatings of the bodies Aand covers extending over the interior surface of the bodiesand covers and extending over the searning flanges of theV bodies and covers to serve as a packing for the folded seams, substantially as specified.

2. The process of making seamless drawn can bodies With an interior protective coating extending over the seaming flange of the body consisting ,in first-coating sheets of tin plate in the fiat with lacquer, then baking 15 the sheets and thereby rendering the lacquer fully dry-and hard and firmly adherent and then cutting and drawing the same into can bodies having outstanding seam flanges With said coated surface on the inside, said dry,

20' hard, baked lacquer coating serving in the drawing step to' diminish and neutralize drawinv puckers in the seam iianges of said can bodoie's, substantially as specied 3. The process consisting in first coating sheets of tin plate in the Hat with lacquer,

then baking the same `thereby rendering,

the lacquer fully dry and hard and firmly adhrent and then forming the same into can bodies and covers having seaming flanges with the baked lacquer protective coating extending continuously and unbrokenly over the interior surface thereof, including the' seaming flanges, said hard, dry, baked lac quer coating serving in said drawing step to diminish and neutralize puckers in the seam"langes cf said' bodies and covers, substantially as specified.

GEORGE W. WEBER.

Witnesses: i

L. A.' WELLEs, W7. l). Paris/IERu 

